the fluttering is your wastegate not your blow off valve and it helps your engine its a security device. you cannot hear compressor surge. And if you removed the valve there would be no compressor surge at all cuz when the TB closes it all goes out the hose .

if you want fluttering get an external wastegate and a super quite BPV (DV).

 

Not only can you hear it in the SR20, but you can feel it. Stutters a slight bit on the pedal.

If you remove the Bypass and leave a hole there it will never boost. If you remove it and have a solid pipe it will cause a problem. What part of the pipe lets air out if the valves are gone?

 

Without a DV valve you'll be stalling the turbo each time, thats what the flutter sound is, you hear the blades cut into the air as it stalls, a turbo will take stalling for a while but it will wear it prematurely. This also makes for a more laggy power delivery as you need to wait for the turbo to spin back up each time you let of and accelerate again, not a long wait on the little K but it's still a wait, DV keeps it spinning as you let off so you can boost right away.

The problem you face with the Audi is fueling, you need the DV there to reuse the air already metered by the MAF, without reusing it the car will run rich. Fit the 710N DV to it and relax.